PubMed HealthSearch

Biomedical subjects

M J Fitzgerald

Publications and source records attributed to M J Fitzgerald.

11 recordsLinked to original sources

Early metabolic effects of sepsis in the preterm infant: lactic acidosis and increased glucose requirement.

The effects of sepsis on carbohydrate metabolism were studied in preterm newborn infants (weight > 1.2 kg, appropriate for gestational age) without maternal endocrine problems who were being examined for infection. Plasma glucose, lactate, and insulin concentrations were measured at initial evaluation and then every 8 hours for a total of 48 hours. Blood, urine, and spinal fluid were obtained for culture and counterimmunoelectrophoresis. Dextrose was administered to each patient to maintain glucose levels in the normal range. Dextrose infusion rates were calculated in milligrams per kilogram per minute. Of the 29 infants, 6 had sepsis (positive culture and counterimmunoelectrophoresis results). Infants with sepsis had significant elevations of plasma lactate concentration (p < 0.003) but normal pH. The dextrose infusion rate was also significantly elevated in the infected infants (p < 0.01). No hypoglycemia or hyperglycemia was observed in either group. No significant difference in plasma insulin concentration was observed. We conclude that significant elevations in plasma lactate concentrations and dextrose infusion rate may be early clinical markers of neonatal sepsis in the first 48 hours of life.

Acidosis, Lactic

The structure and source of lingual proprioceptors in the monkey.

The proprioceptive innervation of the tounge has been investigated in the Cynamolgus monkey by silver impregnation methods following unilateral section of lingual, hypoglossal, and cervical nerves. Muscle spindles were constantly present in the intrinsic and extrinsic muscles. They varied greatly in number, averaged half the length of lumbrical spindles, and showed an unusual arrangement of chain fibre nuclei. Other, inconstant proprioceptors included tendon endings, Ruffini endings, Pacinian corpuscles, paciniform and lamellated endings. Topologically, the endings other than spindles were extra-muscular, so that the overall pattern of proprioceptive innervation resembled that of skeletal muscle in general. Lingual nerve section was without apparent effect on the proprioceptors. Section of the hypoglossal nerve at its point of entry into the tongue caused severe depletiion of ipsilateral proprioceptors and of fusimotor nerves. In the anterior tongue there was evidence of transmedian overlap by efferent and afferent axons contained in the hypoglossal nerve. Hypoglossal section at the skull base caused degeneration of fusimotor nerves but not of proprioceptors. Section of (a), the connexion of C2-C3 ventral rami with the hypoglossal, together with section of (b), the ramus descendens hypoglossi, coused depletion of lingual proprioceptors; again there was evidence of transmedian overlap. Procedures (a) or (b) alone had a lesser effect. It was concluded that lingual proprioceptive afferent fibres occupy the distal hypoglossal nerve, leaving it in the ramus descendens and in the C2-C3 connexion to enter the spinal cord via nerves C2 and C3.

Animals